Javascript 炮口环异常

我正在尝试在localhost中安装mailgun PHP sdk，以便使用composer（完成）发送邮件。当我发送邮件时，我得到了一个异常的戒指

    Fatal error: Uncaught exception 'GuzzleHttp\Ring\Exception\RingException' with message 'cURL 
    error 60: SSL certificate problem: unable to get local issuer certificate' in C:\xampp\htdocs\
yahavi\frontend\public\mailgun-php-master\vendor\guzzlehttp\ringphp\src\Client\CurlFactory.php:127
 Stack trace: #0 C:\xampp\htdocs\yahavi\frontend\public\mailgun-php-master\vendor\guzzlehttp\ringphp\src\Client\
        CurlFactory.php(91):GuzzleHttp\Ring\Client\CurlFactory::createErrorResponse(Array, Array, Array) #1`enter code here` C:\xampp\htdocs\yahavi\frontend\public\mailgun-php master\vendor\guzzlehttp\ringphp\src\Client\CurlHandler.php(96): GuzzleHttp\Ring\Client\CurlFactory::createResponse(Array, Array, Array, Array, Resource id #65) #2 C:\xampp\htdocs\yahavi\frontend\public\mailgun-php-master\vendor\guzzlehttp\ringphp\src\Client\CurlHandler.php(68): GuzzleHttp\Ring\Client\CurlHandler->_invokeAsArray(Array) #3 C:\xampp\htdocs\yahavi\frontend\public\mailgun-php-master\vendor\guzzlehttp\ringphp\src\Client\Middleware.php(54): GuzzleHttp\Ring\Client\CurlHandl in C:\xampp\htdocs\yahavi\frontend\public\mailgun-php-master\vendor\guzzlehttp\guzzle\src\Exception\RequestException.php on line 51